Rock drill



Oct. 19 1926.

C. C. HANSEN ROCK DRILL Filed July 10, 1925 "'INVENTOR. 6602405 6H0): dc)

HIS ATTO 1" EY- Patented Oct. 19, 1926.

UNITED STATES PATENT OFFICE.

CHARLES C. HANSEN, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RAND COMPANY, OF JERSEY CITY, NEXV JERSEY, A CORPORATION OF NEW JERSEY.

R0 GK DRILL.

Application filed July 10, 1925. Serial No. 42,646.

This invent-ion relates to rock drills, but more particularly to a fluid actuated rock drill of the hammer type in which the inlet and compression relief are controlled by in dependent valves, the main free exhaust being controlled by the piston.

The objects of the invention are to enable the fluid actuated inlet and compression relief valves to be conveniently located rearwarclly of the cylinder in the back head parts of the machine with the compression relief valve between the inlet valve and the cylinder.

Another object of the invention is to enable such construction to be carried out without materially lengthening the machine.

The invention is shown in one of its preferred forms in the accompanying drawings, in which Figure 1 is a longitudinal sectional. elevation of so much of a rock drill as will serve to illustrate the invention,

Figure 2 is a similar view taken on a section at right angles to the section on which Figure 1 is taken, and

Figure 3 is a transverse view partly in section taken on the line 3-3 of Figure 2 looking in the direction of the arrows.

Referring to the drawings, the cylinder A having the free exhaust portB located centrally thereof is provided with the piston G controlling said exhaust port. The front head D, the back cylinder Washer E, the head block F and the back head G are held together by the usual side bolts H. The shank J of the drill steel projects into the front head in position to be struck by the shank K of the hammer.

The supply of pressure fluid to the machine is controlled by a suitable throttle valve L conveniently located in the back head and the inlet to both ends of the cylinder is controlled. by the fluid actuated inlet valve O in the valve box P located in the back head G rearwardly of the cylinder. The valve box P is formed with a rectangular chamber Q, and is provided with a cover plate R having the inlet opening S. communicating with the inlet passage T in the back head.

The valve O is in the form of a rectangular hollow block bodily slidable longitudinally in the rectangular chamber Q of the valve box P and this valve is constructed substantially like the valve disclosed in my copending application, Serial No. 31,185, filed May 20, 1925, in which the details of construction are covered.

Pressure fluid entering through the inlet passage T pastes over one end of the valve as shown in Figure 1 through the port U in the valve box, thence through the ports V and ll in the head block and cylinder washer, and thence through the port X to the rearward end of the cylinder for driving the piston forward. After the piston has uncovered the exhaust port B, the pressure on the face Y of the valve O is reduced and pressure fluid under compression acting against the face Z of the valve causes the valve to move to its opposite position, thus admitting fluid over the face Z of the valve through the passage (4 in the valve box and through the ports 7) and c in the head block and cylinder washer and the passage cl in the cylinder to the inlet port 6 at the forward end of the cylinder to drive the piston rearwardly from which point the cycle is repeated.

The compression relief valve 7 is in the form of an oscillating plate distributing from the center towards both ends and located between the inlet valve O and the cyl inder, in the cylinder washer E. The valve 7 oscillates on a pin 7 and controls exhaust ports h and j conveniently located in the head block F. The port 0 in the back cylinder washer E as shown in Figure 3 extends underneath one end 7:: of the valve f so that as the piston moves forwardly, the compression in the forward end of the cylinder is relieved through the port 6, passage 6, port '0 and thence over the end 7: of the valve 7 to the relief port it as indicated in Figure The relief valve f is maintained in the position indicated in Figure 2- during the forward stroke of the piston, due to live pressure fluid through the port 19 leading to the rearward end of the cylinder. On the return rearward stroke of the piston, live pressure holds the end of the relief valve f closed and compression is relieved through the port 79 and over the end 9 of the relief valve to the exhaust port j.

I claim:

1. In a fluid actuated rock drill, the combination of a cylinder and reciprocating piston, a free exhaustport located centrally of the cylinder and controlled by the piston, a valve box having a rectangular chamber lo lOO cated rea'rwardly of the cylinder, a compression actuated inlet valve in the form of a rectangular hollow block bodily slidable longitudinally in said valve box, inlet ports forthe ends of the cylinder controlled only by said inlet valve, and a compression actuated compression relief valve in the form of a thin flat oscillating plate located between the said inlet valve and the cylinder.

2. in a fluid actuated rock drill, the combination of a cylinder and reciprocating piston, a rice exhaust port located centrally of the cylinder and controlled by the piston, a valve box having a rectangular chamber located rearwardly of the cylinder, a compression actuated inlet valve in the form of a rectangular hollow block slidable longitudinally in said valve box, inlet ports for the ends of the cylinder controlled only by said inlet valve and a compression actuated compression relief valve in the form of a thin, fiat oscillating plate, tapering from the center towards each end and located between the inlet valve and the cylinder with its axis of oscillation at right angles to the longitudinal axis of the rock drill.

In testimony whereof I have signed this specification.

CHARLES C. HANSEN. 

